了解同源四倍体不育的调节对于利用基因组缓冲能力的强大优势至关重要,生物多样性,和同源四倍体水稻的杂种优势。miRNAs在生育力调节中起着至关重要的作用,然而,关于它们在四倍体水稻中的生殖作用和靶基因的信息仍然有限。这里,我们使用了三个四倍体系,H1(肥沃),HF(肥沃),和LF(无菌),研究细胞学特征并确定与同源四倍体不育相关的因素。LF显示异常减数分裂,导致花粉繁殖力和生存力低,与H1和HF相比,最终导致很少的施肥和低结实率。RNA-seq揭示了30个与同源四倍体花粉不育相关的miRNA候选靶标对。这些对显示出相反的表达模式,可育系(H1和HF)和不育系(LF)之间的差异表达。qRT-PCR证实miR9564,miR528和miR27874在H1和HF的花药中高表达,而在LF中不高表达。而在他们的目标中获得了相反的结果(ARPS,M2T,和OsRPC53)。单倍型和表达模式分析显示,ARPS在与LF相同的MIR9564(miR9564的前体)单倍型的品系中特异性表达。此外,双重GFP检测证实miR9564抑制ARPS-GFP的荧光信号。ARPS的过度表达显著降低了新四倍体水稻的结实率(59.10%)和花粉育性(50.44%),表明ARPS在同源四倍体花粉不育中起重要作用。这项研究提供了对具有不同育性的四倍体系的细胞学特征和miRNA表达谱的见解,阐明miRNA在多倍体水稻中的作用。
Understanding the regulation of
autotetraploid sterility is essential for harnessing the strong advantages in genomic buffer capacity, biodiversity, and heterosis of
autotetraploid rice. miRNAs play crucial roles in fertility regulation, yet information about their reproductive roles and target genes in tetraploid rice remains limited. Here, we used three tetraploid lines, H1 (fertile), HF (fertile), and LF (sterile), to investigate cytological features and identify factors associated with
autotetraploid sterility. LF showed abnormal meiosis, resulting in low pollen fertility and viability, ultimately leading to scarce fertilization and a low-seed setting compared to H1 and HF. RNA-seq revealed 30 miRNA-candidate target pairs related to
autotetraploid pollen sterility. These pairs showed opposite expression patterns, with differential expression between fertile lines (H1 and HF) and the sterile line (LF). qRT-PCR confirmed that miR9564, miR528, and miR27874 were highly expressed in the anthers of H1 and HF but not in LF, while opposite results were obtained in their targets (ARPS, M2T, and OsRPC53). Haplotype and expression pattern analyses revealed that ARPS was specifically expressed in lines with the same haplotype of MIR9564 (the precursor of miR9564) as LF. Furthermore, the Dual-GFP assay verified that miR9564 inhibited the fluorescence signal of ARPS-GFP. The over-expression of ARPS significantly decreased the seed setting rate (59.10%) and pollen fertility (50.44%) of neo-tetraploid rice, suggesting that ARPS plays important roles in
autotetraploid pollen sterility. This study provides insights into the cytological characteristic and miRNA expression profiles of tetraploid lines with different fertility, shedding light on the role of miRNAs in polyploid rice.